Faqs

An ISBN is an International Standard Book Number. ISBNs consist of 13 digits. The number is calculated using a specific mathematical formula and includes a check digit to validate it.

What is an ISBN used for?

An ISBN is essentially a product identifier used by publishers, booksellers, libraries and internet retailers and other supply chain participants for ordering, listing, sales records and stock control purposes. The ISBN identifies the registrant as well as the specific title, edition and format.

Why should I use an ISBN?

If you are a publisher or bookseller it may be in your own interest as you want to sell books. If your books cannot be ordered and distributed by ISBN and if they are not listed in Books in Print type listings you may find that your books do not sell. People will assume your books do not exist, and even if they do know they exist they may consider it too much of a bother to handle them since they will need to do so using full title, manual ordering.

Do I have to have an ISBN?

From the point of view of the international ISBN system there is no legal requirement to have an ISBN, and it conveys no legal or copyright protection. In a number of countries, though, the use of ISBN is prescribed by law.

Do books need an ISBN if they are not going to be sold?

It is desirable that all books are identified by ISBNs.

If I change the price of my book, should I assign a new ISBN?

No.

Does a change of format require a new ISBN?

Yes, different formats need different ISBNs.

I am revising a book. Does it require a new ISBN?

A significant change of text requires a new ISBN. If revisions have been made it should state on the verso of the title page that the book is a revised edition and the new ISBN should be printed there.

Does a reprint without change of text or binding require a new ISBN?

No. The original number must be retained, provided the publisher and imprint remain the same.

Do I need a new ISBN when I am reprinting a book with a new title?

Yes, a new title requires a new ISBN.

I am not a publisher – can I still obtain an ISBN?

Yes. For our purposes, a publisher is the group, organisation, company, or individual who is responsible for originating the production of a publication. It is also the person or body who bears the cost/financial risk in making a product available — it is not normally the printer.

What happens if I have used all the numbers under my registrant element?

An additional registrant element can be assigned, allowing for a larger output if necessary. This is an additional registrant element, not a replacement.

If I publish in two or more different file formats (e.g. epub, PDF) should I assign separate ISBNs?

Yes. Each different format of an electronic publication that is published and made separately available should be given a separate ISBN.

Should different versions of the e-book that use the same file format (e.g. epub) have different ISBNs?

If the different versions use the same DRM software (e.g. Adobe ACS4) with substantially the same settings and are interoperable on different devices or software, then a single ISBN should be used. If, however, the same DRM software is used on two versions but with significantly different settings (e.g. one allows printing but the other does not) then each version should have its own separate ISBNs.

If proprietary DRM is used that ties a version to a specific platform, device or software then, if ISBNs are assigned (see 6 below), separate ISBNs should be used for each such version.